Leader of team assigned to study factory's monotonous routine (9)
I believe the answer is:
treadmill
'monotonous routine' is the definition.
(I've seen this in another clue)
'leader of team assigned to study factory's' is the wordplay.
'leader of' says to take the initial letters.
'assigned to' means one lot of letters go next to another.
'study' becomes 'read' (synonyms).
'factory' becomes 'mill' (synonyms).
The first letter of 'team' is 't'.
't'+'read'+'mill'='TREADMILL'
(Other definitions for treadmill that I've seen before include "Daily grind" , "Tiresome job" , "Boring or unending job" , "Form of torture" , "Boring routine; old rotary device" .)